Featured Research

Common link suggested between autism and diabetes: Study implicates hyperinsulinemia in increased incidence of autism

Date:

October 19, 2011

Source:

Rice University

Summary:

A review of the genetic and biochemical abnormalities associated with autism reveals a possible link between the widely diagnosed neurological disorder and Type 2 diabetes, another medical disorder on the rise in recent decades.

Share This

A review of the genetic and biochemical abnormalities associated with autism reveals a possible link between the widely diagnosed neurological disorder and Type 2 diabetes, another medical disorder on the rise in recent decades.

Related Articles

"It appears that both Type 2 diabetes and autism have a common underlying mechanism -- impaired glucose tolerance and hyperinsulinemia," said Rice University biochemist Michael Stern, author of the opinion paper, which appears online in this month's issue of Frontiers in Cellular Endocrinology.

Hyperinsulinemia, often a precursor to insulin resistance, is a condition characterized by excess levels of insulin in the bloodstream. Insulin resistance is often associated with both obesity and Type 2 diabetes.

"It will be very easy for clinicians to test my hypothesis," said Stern, professor of biochemistry and cell biology at Rice. "They could do this by putting autistic children on low-carbohydrate diets that minimize insulin secretion and see if their symptoms improve."

Stern said the new finding also suggests that glucose tolerance in pregnant women may need to be addressed more seriously than it is now.

Stern said he first realized there could be a common link between Type 2 diabetes and autism a few years ago, but he assumed someone else had already thought of the idea.

Stern's lab, which is located at Rice's BioScience Research Collaborative, specializes in investigating the genetic interactions associated with genetic diseases like neurofibromatosis, a disorder in which patients are several times more likely to be afflicted with autism and autism spectrum disorders (ASD) like Asperger's syndrome.

Autism and ASD are neurological disorders that have a strong but poorly understood genetic basis. The U.S. Centers for Disease Control and Prevention estimates that about nine out of 1,000 U.S. children are diagnosed with ASD.

Stern said at least four genes associated with increased frequency in autism are known to produce proteins that play key roles in a biochemical pathway known as PI3K/Tor. Stern said he had been studying a form of abnormal function in the synapses of fruit flies that was remarkably similar to abnormalities observed in rats and mice with defects in a different pathway known as mGluR-mediated long-term depression.

"I had also spent a lot of time thinking about insulin signaling because another project in my lab is an endocrinology project in which we're studying how key proteins involved in insulin signaling affect the timing of metamorphosis in fruit flies," Stern said.

From his studies in both areas, Stern knew two things: PI3K/Tor was the major pathway for insulin signals within cells, and insulin could affect synapses in a remarkably similar way to the mGluR defects associated with autism.

"When I read that the incidence of autism was increasing, and combined that with the fact that the incidence of Type 2 diabetes is also increasing, it seemed reasonable that each increase could have the same ultimate cause -- the increase in hyperinsulinemia in the general population," Stern said. "I didn't do anything with this notion for a few years because it seemed so obvious that I figured everyone already knew this hypothesis, or had tested it and found it was not true."

Stern said he changed his mind a few months ago when a health care consulting firm asked him to provide input about autism.

"In preparing for this interview, I discovered that gestational diabetes was the most important identified maternal risk factor for autism, but that 'no known mechanism could account for this,'" Stern recalled. "When I read this, I was speechless. That's when I realized that this was not obvious to others in the field, so I decided to write this up with the hope that clinicians might become aware of this and treat their patients accordingly."

In writing the article, Stern said he learned that the role of insulin in cognitive function is becoming more widely accepted.

"I was checking to see if insulin was known to affect synaptic function, and I learned that the nasal application of insulin is already being tested to see if it is beneficial for both Alzheimer's and schizophrenia."

Stern said he also found preliminary studies that indicated that low-carb diets were therapeutic for some individuals with autism and ASD.

"Based on what's already in the literature, insulin needs to be taken seriously as a causative element in autism," Stern said. "I hope that clinicians will take the next step and put this to a rigorous test and determine how to best use this information to benefit patients."

Story Source:

The above story is based on materials provided by Rice University. Note: Materials may be edited for content and length.

Featured Research

Mar. 31, 2015  Researchers have illuminated an important distinction between mice and humans: how human livers heal. The difference centers on a protein called PPAR alpha which activates liver ... full story

Mar. 31, 2015  Researchers have recorded the first direct observations of the micro-scale mechanisms behind the ability of skin to resist tearing. The results could be applied to the improvement of artificial skin, ... full story

Mar. 31, 2015  Fewer than half of the physicians trained in the United States in 2013 received formal education or training on the subject of exercise, according to new research. "There are immense medical benefits ... full story

Mar. 31, 2015  Memory and as well as connections between brain cells were restored in mice with a model of Alzheimer's given an experimental cancer drug, researchers report. "With this treatment, cells under ... full story

Mar. 31, 2015  Increasing state alcohol taxes could prevent thousands of deaths a year from car crashes, say researchers, who found alcohol-related motor vehicle crashes decreased after taxes on beer, wine and ... full story

Mar. 31, 2015  Alcoholism takes a toll on every aspect of a person's life, including skin problems. Now, a new research report helps explain why this happens and what might be done to address it. "The clinical ... full story

Mar. 31, 2015  A new population of 'memory' immune cells has been discovered by scientists, throwing light on what the body does when it sees a microbe for the second time. This insight, and others like it, will ... full story

Mar. 31, 2015  Coronary heart disease and stroke, two of the leading causes of death in the United States, are diseases associated with heightened platelet reactivity. A new study in humans suggests an underlying ... full story

Mar. 31, 2015  A new study had researchers seeking answers to why the therapeutic benefit afforded by SSRIs was so limited in children and teenagers. If researchers can uncover the biological mechanisms preventing ... full story

Featured Videos

Solitair Device Aims to Takes Guesswork out of Sun Safety

Reuters - Innovations Video Online (Mar. 31, 2015)  The Solitair device aims to take the confusion out of how much sunlight we should expose our skin to. Small enough to be worn as a tie or hair clip, it monitors the user&apos;s sun exposure by taking into account their skin pigment, location and schedule. Matthew Stock reports.
Video provided by Reuters

Soda, Salt and Sugar: The Next Generation of Taxes

Washington Post (Mar. 30, 2015)  Denisa Livingston, a health advocate for the Dinι Community Advocacy Alliance, and the Post&apos;s Abby Phillip discuss efforts around the country to make unhealthy food choices hurt your wallet as much as your waistline.
Video provided by Washington Post

S. Leone in New Anti-Ebola Lockdown

AFP (Mar. 28, 2015)  Sierra Leone imposed a three-day nationwide lockdown Friday for the second time in six months in a bid to prevent a resurgence of the deadly Ebola virus. Duration: 01:17
Video provided by AFP

Related Stories

Sep. 12, 2014  Over the past five years, several studies have focused on infertility treatment, partly because of the coincidental rise in both the diagnosis of autism and the use of assisted reproduction. A recent ... full story

Aug. 28, 2014  A genetic change in a recently identified autism-associated gene has been identified by researchers, which may provide further insight into the causes of autism. The study presents findings that ... full story

Jan. 27, 2014  A new study finds that the estimated prevalence of autism under the new DSM-5 criteria would decrease only to the extent that some children would receive the new diagnosis of social communication ... full story

Apr. 26, 2012  Maternal age is linked to autism, a new review of studies suggests. While much research has been done to identify potential genetic causes of autism, this analysis suggests that non-heritable and ... full story

ScienceDaily features breaking news and videos about the latest discoveries in health, technology, the environment, and more -- from major news services and leading universities, scientific journals, and research organizations.